关于堆石料三维流变速率的一点注记

原型监测表明面板堆石坝一般存在比较显著的流变现象。针对不同文献给出的堆石料三维剪切流变速率计算式存在差异，笔者以3参数指数流变模型为例对堆石料三维流变速率进行了研究。假设体积流变和剪切流变变化规律不同，首先推导了三维体积流变速率计算公式，然后依据Prandtl-Reuss流动法则可以由Mises屈服函数作为塑性势函数推导获得。为此，采用关联流动法则，同时假设塑性势函数为Mises屈服函数，导出了堆石料三维剪切流变速率计算式。通过将三维流变速率计算式退化为单轴流变速率计算式进行合理性分析，分析表明，本文导出的三维流变速率计算式理论上是严谨的，由此指出相关文献给出的流变速率计算式理论上不严谨。

Note on three-dimensional rheological rate of rockfill material

Rheological phenomenon of the concrete faced rockfill dam can be critical according to prototype monitoring. In view of the three-dimensional shear rheological rate formulas of rockfill material are different in different documents. Three-dimensional rheological rate of rockfill material is studied with the rheological model of 3 parameters as an example. Volume rheology and shear rheology are assumed different. First of all, the three-dimensional volume rheological rate formula is deduced; and then, based on Prandtl-Reuss flow rule, it can be derived by Mises yield function as a plastic potential function. The computational formula of three-dimensional shear rheological rate of rockfill material is derived taking associated flow rule and assuming that the plastic potential function is Mises yield function. The theory of the computational formula of three-dimensional rheological rate is rigorous, since the computational formula of three-dimensional rheological rate can degrade into the computational formula of uniaxial state. Thus it is pointed out that the theory of the computational formula of three-dimensional rheological rate in related papers is not rigorous.